| 摘要 |
1484401 Spinning asbestos yarns TBA INDUSTRIAL PRODUCTS Ltd 18 Feb 1976 [8 March 1975] 9746/75 Heading D1F Fibrous strand or yarn is produced from an aqueous dispersion of (chrysotile) asbestos fibre specified in Specification No. 1484402 by forming e.g. by extrusion, a stream of the dispersion and chilling it e.g. by contact with a flow of cold water, sufficiently to gel the dispersion. The stream may be subjected to variations in tension whilst being chilled e.g. by (usually abrupt) change(s) in the direction of flow. The cohered strand removed from the chilling medium may be subjected to treatment to remove all the residual soap and fatty acid. As shown, a dispersion of asbestos 6 is discharged as a stream 7 through a nozzle 8 onto the surface of chilled water 9 flowing from a header tank 10, over a weir 11 and down an inclined chute 12, optionally through a pool 17, to be collected on a wire-mesh endless belt 13, the separated water being recirculated to tank 10 through a filter 14 and chilling unit 15 by a pump 16. Discontinuities on the surface of the chute 12 may comprise angular or sinusoidal corrugations, as at 20, or transverse rectangular bars, Figs. 2-4 (not shown). The cold water flow has 5-20 times the velocity of the dispersion stream. The collected strand is passed by nip rollers 23 into an oven 24. wherein injected superheated steam removes water and organic residue, and is then wound on a spool 26 for transfer to conventional twisting apparatus. |
